World's Longest Immersed Tunnel: Linking Denmark and Germany
2025-03-10
Denmark and Germany are building the world's longest immersed tunnel, the Fehmarnbelt Fixed Link, set to open in 2029. This 18-kilometer tunnel will more than halve travel times between the two countries and become the world's longest combined road and rail tunnel. The €7 billion+ project uses 89 massive prefabricated concrete sections, each weighing 73,000 tons. Despite some environmental concerns, the project is expected to bring significant economic and environmental benefits, boosting freight and passenger traffic, and reducing carbon emissions.